Charles e



(No Model.)

C. E. S-CRIBNER.

ELECTRIC LIGHT-SWITCH BOARD.

Patented Aug. 2,

i OOO Il UNITED STATES PATENT OEEICE.

CHARLES E. SCRIBNER, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE VESTERN ELECTRIC COMPANY, OF SAME PLACE.

ELECTRIC-LIGHT SWITCH-BOARD.

SPECIFICATION forming part of Letters Patent No. 367,670, dated August 2, 1887.`

Appncann nina Maren 13, naar. serial No. 153,163, (No mount.)

To @ZZ whom it may concern:

Be it known that I, CHAnLEs E. SCEIENEE, a citizen of the United States, residing at Chicago, in the county ot" Cook and State of Illinois, have invented a certain new and useful Improvement in Electric-Light Switch-Boards, (Case 95,) of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

Myinvention relates to switch-boards for strong currents, such as are used in electric lighting, and its object is to prevent accidents by preventing the switchmen from touching the metallic portions ot" the switch-board.

My invention is illustrated in the accompanying drawings, in which- Figure l is a perspective view ot' a portion of an electric-light switchboard embodying` my invention. Fig. 2 is a sectional view of a single spring-jack switch and a connectingplug inserted therein, said plug being the ter-` minal of a heavily-insulated flexible conductingcord. Figs. 3 and 4 are detailed views ot' parts of the plug.

Like parts are indicated by simil-.ir letters of reference in the diti'crcnt tigures.

The frame c of the switch-board may be of wood or other insulating material.

rlhespring-jacks b are attached to the rear side thereof, and the tubes c of the different spring-jacks being countersunk with respect to the face ofthe board. The shank l of the plug is ol" metal, and is adapted to be inserted inthe tube of the spring-jack, as shown in Fig. 2. Thetlexible cord cis heavily insulated, and the handlefof the plug is of rubber and should be as large as the opening on the face ofthe board to any ofthe spring-jacks.

Bymcans of a cord provided with a plug at each end, any two switches upon the switchboard may be connected together, while all met-allie parts of the said switches and connecting devices are covered so as to prevent the possibility of accidental shocks. As the tubes c are back ot' the plane of the face ofthe board,they are practically ont of the reach of accidental contacts at all times.

I claim as new and desire to secure by Letters Patent- 5o 1. The combination, with the countersunk spring-jacks of a switch-board, of plugs insulated, as described, and adapted for insertion into the spring -jacks, whereby all metallic portions ol" the switch are insulated.

2. In a switch-board, -the co1nl.iination,with spring -jacks mounted upon the rear side thereof, the tubes or frames of said springjacks being open at the front of the board, yet countersunk with respect tothe face of the 6o board, and a plug provided with a handle of insulating material of greater diameter than the openings in the face of the board` to the spriug-jacks,whereby all the metal of the plug, as well as all the metal of any given springjack, is entirely covered where the plug is inserted therein.

3. In a switch-board forstrong currents,the combination, with the spring-jacks, of insulated plugs adapted for insertion therein, the 7o diameter of the plug-insulation bcingns great as that of the springyack` entrance, whereby the spring-jack entrance is com pletel y covered by the insulation when the plug is inserted.

1I. The combination,with the switch-board, 75 ot` spring-jacks attached thereto, the metallic portions ot' said spring-jacks being countersunk with respect to the face of the board, substantially as and for thcpurposc specified.

In witness whereof I hereunto subscribe my 8o name this 28th day of February, A. D. 1885.

CHARLES E. SCRIBNER.

` Vitncssos:

GEORGE P. BARTON, F. H. M. CULLooH. 

